Claims
- 1. A process for preparing a product predominant in decabromodiphenylalkane and containing a minor amount of dodecabromodiphenylalkane, the process consisting essentially of: forming a stirrable reaction mass by feeding molten diphenylalkane to a reaction vessel to which aluminum halide catalyst and bromine had been previously charged, the molten diphenylalkane being maintained under a non-oxidizing atmosphere prior to the feeding, and the bromine (i) containing about 10 ppm or less impurities, and (ii) being charged in an amount which provides from about 15 to about 30 moles of bromine per mole of diphenylalkane fed; maintaining the reaction mass at a temperature in the range of from about 15.degree. C. to about reflux during the feeding; subsequent to the feeding, separating from the reaction mass the decabromodiphenylalkane predominant product; and heat treating the separated product for a period of time ranging from 1 to 20 hours and at a temperature within the range of from about 200.degree. C. to about 400.degree. C. which time and temperature are sufficient to form the decabromodiphenylalkane predominant product containing the minor amount of dodecabromodiphenylalkane wherein the minor amount is less than about 20 weight percent based upon the total amount of heat-treated product thus obtained.
- 2. The process of claim 1 wherein the amount of bromine charged provides from about 18 to about 23 moles of bromine per mole of diphenylalkane.
- 3. The process of claim 1 wherein the product is separated from the reaction mass by steam stripping the reaction mass to remove non-entrained bromine therefrom.
- 4. The process of claim 1 wherein the product comprises 90.sup.+ weight percent decabromodiphenylalkane.
- 5. The process of claim 4 wherein the decabromodiphenylalkane is decabromodiphenylethane.
- 6. The process of claim 1 wherein the diphenylalkane reactant is 1,2-diphenylethane.
- 7. The process of claim 6 wherein the 1,2-diphenylethane is at a temperature of from about 55.degree. C. to about 80.degree. C. when fed to the reaction vessel.
- 8. The process of claim 7 wherein the 1,2-diphenylethane is fed under a nitrogen atmosphere.
- 9. A process for preparing a product predominant in decabromodiphenylethane and containing a minor amount of 1,2-dibromo-bis-pentabromophenylethane, the process consisting essentially of: forming a stirrable reaction mass by feeding molten 1,2-diphenylethane to a reaction vessel to which aluminum halide catalyst and bromine had been previously charged, the molten 1,2-diphenylethane being maintained under a non-oxidizing atmosphere prior to the feeding, and the bromine (i) containing about 10 ppm or less impurities, and (ii) being charged in an amount which provides from about 18 to about 23 moles of bromine per mole of 1,2-diphenylethane fed; maintaining the reaction mass at a temperature in the range of from about 15.degree. C. to about reflux during the feeding; subsequent to the feeding, separating from the reaction mass the decabromodiphenylethane predominant product; and heat treating the separated product at a temperature in the range of from about 200.degree. C. to about 280.degree. C. for 1 to 20 hours so as to form the decabromodiphenylethane predominant product containing the minor amount of 1,2-dibromo-bis-pentabromophenylethane wherein the minor amount is less than about 20 weight percent based upon the total amount of heat-treated product thus obtained.
- 10. The process of claim 9 wherein the product comprises 90.sup.+ weight percent decabromodiphenylethane and at least 0.5 weight percent 1,2-dibromo-bis-pentabromophenylethane.
- 11. The process of claim 10 wherein, during the 1,2-diphenylethane feed the reaction mass is at a temperature within the range of from about 15.degree. C. to about reflux.
- 12. The process of claim 11 wherein the product is separated from the reaction mass by steam stripping the reaction mass to remove non-entrained bromine therefrom.
Parent Case Info
This application is a division of application Ser. No. 07/559,655, filed Jul. 30, 1990, now pending.
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4287373 |
Garman et al. |
Sep 1981 |
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4327227 |
Ayres et al. |
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4740629 |
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GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
559655 |
Jul 1990 |
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